U.S. Pat. No. 4,070,189 relates to antistatic compositions comprising a highly cross-linked vinylbenzyl quaternary ammonium polymer and a hydrophobic binder. This patent suggests that since the solvent for applying the coating must both disperse the antistatic polymer and dissolve the binder, mixtures of solvents may be desirable. The preferred solvent combination disclosed is acetone/methanol and methanol/propylene chloride/2-methoxyethanol. Subsequently, it has been found that a mixture of acetone, methanol, and methyl chloroform gave particularly good results with regard to coating latitude and to the elimination of an imperfection known as "bloom" which appears as a haze under specular lighting.
Because of environmental reasons, solvents utilizing halogenated hydrocarbons in any degree are suspect. Therefore, in order to avoid any question of environmental degradation, it is desired to replace the methyl chloroform used in the solvent mixture without an accompanying degradation to the photographic films. This is not a simple task because the methyl chloroform in conjunction with the mixture of solvents indicated above gives particularly good results for a variety of reasons as expressed. Thus, one cannot simply remove the methyl chloroform from the solvent formulation or substitute any known solvent in its place and expect to achieve substantially the same results.